1. Field
The disclosure relates to a brake actuator unit. More particularly, the disclosure relates to a brake actuator unit capable of improving the pedal feeling.
2. Description of the Related Art
In general, an active hydraulic booster (AHB) includes a brake actuator unit. When a driver steps on a brake pedal, the brake actuator unit detects displacement of the brake pedal from a pedal displacement sensor and an electronic control unit (ECU) calculates wheel pressure to control pressure of each wheel through an independent feedback control.
In such a brake actuator unit, if the driver steps on the brake pedal, an input shaft is moved and the ECU detects the movement of the input shaft, so working fluid stored in an accumulator is transferred to the master cylinder to generate the liquid pressure in the master cylinder. However, if the pressure of the master cylinder is changed during the regenerative braking operation, the pressure variation may be directly transferred to the brake pedal, thereby deteriorating the pedal feeling. In addition, a simulator chamber must be additionally installed to improve the pedal feeling, so the size of the brake actuator unit is unnecessarily increased.